Prevalence of pathogenic Escherichia coli virulence genes in raw and domestically treated waters in Dhaka city: An overlooked health hazard analysis

Abstract

Diarrhea is one of the leading causes of infant mortality in developing countries like Bangladesh. This study aims to detect the presence of fecal coliform in the supplied water and treated water in the households of Dhaka city. The samples were collected from October 2018 till August 2019. The samples were further subjected to PCR to detect the presence of diarrheagenic E.coli. Nine primer pairs were used detect the five diarrheagenic strains of E.coli (EPEC, EHEC, ETEC, EAEC and EIEC). Fecal coliform counts produced by supplied water samples and treated water samples were categorized into the following: 0 count, 1-5 count, 6-30 count, 31-100 count, >100 count. Fecal coliform was not detected in 29.46% of the supplied water samples. On the other hand, 18.26% of the supplied water samples produced a fecal coliform count of greater than 100. 12.86% of supplied water samples have a count varying between 1 to 5, 27.81% of the samples have a 6 to 30 fecal coliform count and 11.62% of the samples have 31 to 100 fecal coliform count. ETEC was detected in 14.94% of the samples while EHEC was detected in 12.24% of the supplied water samples. 3.94% of the supplied water samples had EAEC. EPEC and EIEC were detected in 1.45% of the supplied water samples only. 52.62% of the treated water samples did not produce any fecal coliform count, while 1.65% of the treated water samples had a fecal coliform count greater than 100. 14.88%, 21.49% and 9.37% of the treated water samples had a fecal coliform count of 1-5, 6-30 and 31-100 respectively. ETEC, EHEC and EAEC were detected in 3.03%, 2.75% and 0.83% of the treated water samples respectively. EPEC and EIEC were not detected in the treated water samples.